This invention is concerned with a method for enhancing the properties of carbon-carbon fibre composite materials and structures, more particularly with a method for the restoration and/or upgrading of defective carbon-carbon fibre composites.
Carbon-carbon fibre composite materials and structures, e.g. comprising a matrix of carbon embedded in a carbon fibre structure, are used inter alia as frictional materials in brakes and clutches. In such applications these materials may experience frictional and oxidative wear, leading to loss of both physical dimensions and physical properties such as strength and thermal capacity. As a result of degradation of their physical properties such materials may have to be discarded as defective when only partly worn in terms of their physical dimensions.
Defective or substandard carbon-carbon fibre composites may also result from faulty manufacturing processes or as a result of stresses imposed when used in applications other than as frictional materials. Thus, for example, faulty manufacturing processes often lead to low density products with fine crazing and shrinkage cracks; such materials typically exhibit poor mechanical properties and low thermal conductivity and diffusivity.